The synopsis of "Black Lightning," according to Variety's Jacob Bryant:
The series will follow Pierce — now retired from his crime-fighting days — who’s pulled back into vigilante life as one daughter is hell-bent on justice and the other is being recruited by a local gang.
In the "Super-Team Family" DC comic book crossover, Black Lightning beat up Power Man pretty badly. Black Lightning said:
You may be bulletproof, Cage, but let's see how long those lungs of yours keep you alive when this drain fills up with water.
Lightning's electrokinetic abilities are more creative and scientific. He can also generate force fields, fly and is proficient at martial arts. He'll end up saving the day the same way Flash saves the day in the "The Flash"—with his wits and using science to show off the cool things he can do with electromagnetic manipulation.
Umm.... but Luke Cage is bulletproof. BULLETPROOF.
According to IMDB, the synopsis of "Luke Cage" series:
Given superstrength and durability by a sabotaged experiment, a wrongly accused man escapes prison to become a superhero for hire.
Power Man is wrongfully convicted, and ends up getting his abilities from an inhumane experiment in prison. His origin story speaks to the prison-industrial complex and the U.S.'s history of experimenting on or controlling Black bodies. Nevertheless, he turned it all into a positive.
Luke got some pretty cool powers—impenetrable skin, invulnerability, superhuman strength and superhuman durability. He used his abilities to help others, and even got paid doing it. So explain again how Luke Cage can be stopped? Okay.